后蕊苣苔属花粉形态的补充研究

Supplemental study on pollen morphology of Opithandra(Gesneriaceae)

关键词:  苦苣苔科  后蕊苣苔属  花粉形态  系统分类

Key words:  Gesneriaceae  Opithandra  pollen morphology  taxonomy

摘要:

首次对后蕊苣苔属(Opithandra)文采后蕊苣苔(O. wentsaii)、龙南后蕊苣苔(O. burttii)和裂檐苣苔(O. pumila)的花粉进行扫描电镜研究。结果表明:三者花粉形状与外壁纹饰差异显著。在前人研究基础上,综合花粉形状及外壁纹饰特征,将后蕊苣苔属花粉分为四大类群:第一大类群包括O. burttii、O. sinohenryi、O. primuloides和O. fargesii,该类群花粉近球形,网状纹饰,网脊较宽,宽度不均匀; 第二大类群包括 O. acaulis和O. pumila,该类群花粉近球形,网状纹饰不明显,刺密且显著; 第三大类群包括O. dalzielii、O. cinerea和O. dinghushanensis,该类群花粉近球形或扁球形,网状纹饰,网脊较窄,宽度均匀; 第四大类群包括O. wentsaii和O. obtusidentata,该类群花粉长椭圆球形,网状纹饰,网脊较窄,宽度均匀。结果与王文采对该属的分类系统不完全一致,对该属分类提出一些建议。

Abstract:

Pollen grains of Opithandra wentsaii,O. burttii and O. pumila were firstly examined by SEM. The pollen morphologies of them were significantly different from each other. Based on previous research,according to the pollen shape and exine ornamentation,pollen grains of this genus can be divided into 4 groups:(1)pollen is subspheroidal,wide muri and uneven width of muri,including O. burttii,O. sinohenryi,O. primuloides and O. fargesii;(2)pollen is subspheroidal,obscure reticulation with distinct spinulate,including O. acaulis and O. pumila;(3)pollen is subspheroidal or oblate,narrow muri and even width of muri,including O. dalzielii,O. cinerea and O. dinghushanensis;(4)pollen is long ellipsoid,narrow muri and even width of muri,including O. wentsaii and O. obtusidentata. Our result disaccords with Wang's classification system. We put forward classified advice to the genus.